The Sonographic Squeeze Test: Assessing the Reliability of the Dorsal Scapholunate Ligament

BackgroundThere is no universally accepted imaging method to diagnose scapholunate ligament (SLL) tears. Our aim was to use sonography to evaluate the reliability of SLL length at baseline compared with a standardized dynamometer maneuver in healthy normals.Materials and methodsSonographic exams from 31 consented asymptomatic patients between 18 years and 45 years of age were collected on a total of 60 wrists. The length of the SLL was measured superficially and at a depth of 3.0 mm during static and dynamic squeeze maneuver. Inter- and intraexaminer reliability was performed using the intraclass correlation coefficient (ICC).ResultsThe superficial ligament length measured 0.60 cm ± 0.11 cm with a deep measurement of 0.20 cm ± 0.06 cm. Dynamic evaluation revealed superficial and deep measurements at 0.62 ± 0.12 cm and 0.20 ± 0.06 cm, respectively. There was no significant difference between the SLL length at rest and during the squeeze test. The interexaminer and intraexaminer reliability was rated at fair to very good.ConclusionThe evaluation of the dorsal SLL by sonographic squeeze test is reliable. Future studies will apply this method to suspected SLL tears.